Reusable beer keg

ABSTRACT

A reusable beer keg is disclosed comprising a hollow beer keg body with a dispenser tube assembly having a dispenser valve, dispenser tube, and a disposable bladder. The dispenser valve is releasably attached to a top portion of the keg body and the dispenser tube and bladder extend into the interior of the keg body. When beer flows through the open dispenser valve and into the bladder, the beer causes the bladder to unfurl until it contacts the inside surface of the keg body. When the beer keg has been emptied it can be returned to the brewery for reuse by cleaning the dispenser valve, dispenser tube and disposing of the used bladder. The beer keg body does not need to be cleaned, however, because the beer only comes in contact with the disposable bladder and not the keg body. The beer keg parts can then be reassembled, using a new bladder in place of the used bladder.

PRIORITY

This application is a National Stage Application under 35 U.S.C. §371 ofPCT/US2010/001008 filed Apr. 1, 2010, which claims the benefit of U.S.Provisional Application 61/211,728 filed Apr. 1, 2009.

TECHNICAL FIELD

This application relates to pressurized beer containers or kegs and,specifically, to pressurized beer containers that are designed to bereturned to a brewery or bottler for cleaning and refilling.

BACKGROUND

Most breweries presently supply beer to commercial establishments, likerestaurants and bars, in stainless steel kegs. In the United States afull keg is a 15.5 gallon U.S. gallon barrel, sometimes referred to as ahalf-barrel. In European countries the keg most comparable to the USfull keg is a keg having a size of 50 liters (13.21 gal). Normally thekeg will have long dispenser-like tube extending from the top of the kegto just above it's inside bottom surface. In addition, a pressurizingvalve is typically connected to the top of the keg and dispenser tubeand is used with a tap valve to pressurize the beer within the keg,causing the beer to flow from the bottom of the keg and up through thedispenser tube and tap, and into a serving container.

Stainless steel beer kegs are expensive to manufacture and are intendedto be returned by the commercial establishment to the brewery forcleaning and refilling. An additional expense arises from that fact thatafter the same stainless steel keg has been returned to the breweryabout 20 times, the keg must be reworked to remove dents that wouldotherwise reduce the internal volume to an unacceptable degree. Anotherwell recognized expense to the brewery industry is that a largepercentage of stainless steel kegs are never returned due to theft,causing the brewery to incur substantial economic loses. Severalattempts have been made to reduce these expenses by producing relativelyinexpensive plastic and/or composite beer kegs that are not returned tothe brewery, but are either disposable or can be sent to a plasticrecycling facility for grinding into raw material for use in theproduction of other plastic articles. (See for example, U.S. Pat. No.6,666,358). In this regard, although disposable kegs certainly eliminatethe economic costs associate with the theft of stainless steel kegs, aswell as the cost of cleaning the kegs, disposable kegs have other costsassociated with the contamination of the environment. Further, even ifthe kegs are sent to a plastic recycling facility, there are theconsiderable costs associated with collecting, sorting, cleaning andgrinding the kegs into a reusable form that can then be used tomanufacture other plastic products.

Accordingly what is needed is a reusable beer keg that is substantiallyless expensive to manufacture than a stainless steel keg but can bereturned and refilled by the brewer just like a stainless steel keg. Inaddition, the reusable beer keg should be produced in a manner thatwould make it less desirable to persons who might be inclined to stealit. As will be apparent from the description that follows, the reusablebeer keg of the present invention satisfies these needs and providesother unique and desirable features.

SUMMARY

A reusable beer keg is disclosed which comprises a hollow beer keg bodywith the keg body having a keg opening for providing access to theinterior of the keg body;

-   -   a dispenser valve; a dispenser tube with the top end of the tube        connected to the dispenser valve; a disposable bladder having a        bladder opening, with the dispenser tube disposed through the        bladder opening and extending into the interior of the bladder        and with the bladder opening releasably engaged with the        dispenser valve, thereby forming a dispenser tube assembly; and        whereby the dispenser tube assembly can be disposed through the        keg opening, with the dispenser valve releasably attached to the        keg body; and the dispenser valve can be operated to supply beer        to the interior of the bladder and then operated to supply gas        pressure to the beer, causing the beer to flow through the        dispenser tube and dispenser valve.

A method for using a reusable beer keg is also disclosed. comprising thesteps of:

-   -   a) providing a hollow beer keg body with the keg body having a        keg opening for providing access to the interior of the keg        body;    -   b) assembling a dispenser tube assembly by disposing a dispenser        tube through an opening through a disposable bladder, with one        end of the dispenser tube extending into the interior of the        bladder, and with the bladder opening releasably secured to a        dispenser valve connected to the other end of the dispenser        tube;    -   c) disposing the dispenser tube assembly through the keg body        opening such that the dispenser valve releasably engages the keg        body and the dispenser tube extends into the interior of the keg        body, thereby creating the reusable beer keg;    -   d) dispensing beer into the interior of the bladder;    -   e) dispensing pressurized gas into the interior of the bladder,        causing the beer to flow up through the dispenser tube;    -   f) disassembling the reusable beer keg after it has dispensed        the beer by releasing the dispenser valve from its engagement        with the keg body, removing the dispenser tube assembly from the        interior of the keg body, and releasing the bladder from its        engagement with the dispenser valve;    -   g) disposing of the disposable bladder;    -   h) cleaning the dispenser valve and dispenser tube; and    -   i) reassembling the reusable beer keg as in steps (b) and (c)        above by reusing the keg body, cleaned dispenser valve and        dispenser tube, and using a new disposable bladder.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the reusable beer keg with the dispensertube assembly partially disposed into the interior of the keg body.

FIG. 2 is a perspective view of the dispenser tube assembly

FIG. 3A is a perspective view of the dispenser tube and dispenser valveand FIG. 3B is partial cross-sectional plan view of the dispenser tubeand dispenser valve.

FIG. 4 is an illustration of the disposable bladder in an unfurledstate, including a depiction of the bladder fitment.

FIG. 5A is a perspective illustration of the dispenser tube anddispenser valve partially disposed through the bladder fitment andextending into the interior of the bladder; FIG. 5B is anotherperspective illustration of the dispenser tube assembly; FIG. 5C is apartial cross-sectional plan view of the dispenser tube assembly; andFIG. 5D is side view of is another embodiment of the dispenser tubeassembly.

FIG. 6A is a partial cross-section of a front perspective view of thereusable beer keg with the dispenser tube assembly releasably connectedto the keg body; and FIGS. 6B and 6C are partial perspective views of atop portion of the keg body, illustrating the dispenser valve in anunlocked and locked position, respectively.

FIG. 7 is the same illustration as in FIG. 6A but further illustratesthat the bladder has started to expand as beer flows into the bladderthrough the dispenser valve.

FIG. 8 is the same illustration as in FIG. 7 but further illustratesthat the bladder has expanded so as to contact the inner surface of thekeg body when the bladder is full of beer.

FIG. 9A is a partial cross-section of the dispenser tube assembly withthe dispenser valve closed and FIG. 9B illustrates the dispenser tubeassembly with the dispenser valve open.

FIG. 10 A is a side view of two reusable beer kegs, with one keg stackedabove the other keg and the kegs secured together with a locking strap;and FIG. 10B is a partial cross-sectional diagram of the beer kegsillustrated in FIG. 10A further illustrating the arcuate surfaces formedon the bottom surface of one keg and on top surface of the other keg.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The reusable beer keg 1 of the present invention is generallyillustrated in the perspective view of FIG. 1. Beer keg 1 has agenerally cylindrical shape and is intended to approximately conform tothe size and shape of commonly used stainless steel beer kegs, andspecifically to either a 15.5 U.S. gal or a 50 L European stainlesssteel keg. Preferably, beer keg 1 comprises a hollow one-piece keg body2 that is molded from a plastic material utilizing a single or unitarymold process in order to form the one-piece keg body in which thecomposition of the plastic material forms a continuous and homogenousunit. Preferably, the plastic material can be a polyethylene elastomeror a polyurethane elastomer. For example, an acceptable plastic can beTADCO 37452, a Shore D56 polyurethane rotomolding product. Preferably,the molded keg body 2 has a nominal wall thickness of approximately 0.2inches; however, the keg wall thickness can be increased in at least twoareas within the molded keg body 2 where additional structural integrityis needed. First, the keg wall thickness can be increased preferably byproviding two integral circumferential bands that extend around theperimeter of keg body 2 and are approximately 0.4 inches thick, with thebands being formed during the unitary molding process of keg body 2.Second, the thickness of the top and bottom sections of keg body 2 canbe increased preferably by providing eight elongate members that extendradially within the molded top and bottom portions of keg body 2, witheach elongate member being approximately 0.4 inches thick and with themembers also being formed during the unitary molding process of keg body2. Alternatively, the keg body can be molded into two sections: a lowerbody section and a lid section, with the two sections adapted to beconnected so as to form the keg body. Keg body 2 has an annular opening2A through its top end that provides access to the interior of thehollow keg body. Keg body 2 also includes a top cylindrical member 3Athat is attached to the top outside surface of keg body 2 and surroundsannular opening 2A. The keg body 2 further includes a bottom cylindricalmember 3B that is attached to the bottom outside surface of keg body 2.Preferably, top and bottom cylindrical members, 3A and 3B, are made ofthe same plastic material that is used to mold keg body 2 and eachcylindrical member is attached to keg body 2 by gluing the member to theoutside surface of the body. A valve attachment collar 4 is attached,preferably by gluing, to the outside surface of the top portion of kegbody 2 and is positioned such that the circularly shaped opening withinthe collar is positioned above and encircles keg opening 2A. The figurealso illustrates a dispenser tube assembly 10 that has been partiallydisposed into the interior of the keg body 2 by passing the assemblythrough valve attachment collar 4 and keg opening 2A.

As illustrated in FIG. 2, dispenser tube assembly 10 comprises: adispenser valve 11 that is used to regulate in the inflow and outflow ofbeer; an expandable and disposable bladder 13 that is illustrated withtwo of the bladder's opposing sides rolled up or furled into a pair ofopposing elongate tubes 13A and 13B, with the pair of tubes unfurling asbeer flows through dispenser valve 11 and into bladder 13; and adispenser tube 12 (shown in FIG. 3) that is disposed within the interiorof bladder 13 and utilized to remove pressurized beer from the expandedbladder. Dispenser tube 12 is attached to dispenser valve 11 byconnecting a top end of the dispenser tube to the interior of thedispenser valve, and bladder 13 is releasably attached to dispenservalve 11. A more detailed description of the dispenser valve 11 and itsattachment to dispenser tube 12 and bladder 13 is presented inconnection with the discussion of FIGS. 3B, 5C, 9A and 9B. As shown inFIG. 1, in order to use beer keg 1, the dispenser tube assembly 10 isinserted into keg body 2 by disposing the assembly through keg bodyopening 2A and valve attachment collar 4, with assembly 10 extendinginto the interior of keg body 2.

FIGS. 3A and 3B present a more detailed illustration of dispenser valve11 and dispenser tube 12. Dispenser valve 11 comprises an annular valvebody 20, annular bottom flange 21, including a pair of radiallyextending cantilever arms 29, annular valve seal 23, annular valve innerseat 24, valve outer spring 25, an O-ring 26, valve locking member 29,and an inlet port 28. Valve body 20, valve inner seat 24, and valveouter spring 25 are each preferably made of 316 stainless steel, andvalve seal 23 and resilient O-ring 26 are each preferably made ofViton®, respectively. The top end of dispenser tube 12 is connected tothe inside of valve body 20 with outer valve spring 25 disposed aroundthe outside surface of the dispenser tube. A valve inner spring 27 isconcentrically disposed within the interior of dispenser tube 12 withthe bottom of the spring in contact with an annular ledge and the top ofthe spring is in contact with valve seat 24. Dispenser tube 12 and innervalve spring 27 are preferably made of 316 stainless steel. Theoperation of the dispenser valve will be described in connection withFIGS. 9A and 9B.

FIG. 4 presents an illustration of the disposable bladder 13 before twoof its opposite sides are rolled up or furled into two opposing furledtubes, 13A and 13B. In one embodiment, bladder 13 comprises two flatsheets of a material, with the perimeter edges, including opposite edges16A and 16B, of the flat sheet material welded together in order tocreate the bladder for containing the beer. Preferably, the sheetmaterial has the characteristics of being flexible, foldable,impermeable to beer, substantially impermeable to oxygen, andsubstantially inert when in contact with beer. Preferably, disposablebladder 13 is made of 75 gauge, extrusion metalized material,manufactured by Biax Fiber Film Corporation; however, other suitablematerials that are also flexible, foldable, impermeable to beer,substantially impermeable to oxygen, and substantially inert when incontact with beer could also be used. Regardless of the type of materialthat is used to form the bladder, a top portion of bladder 13 contains abladder opening, and an annular member 15, preferably made of nylon, isattached to the outside surface of the bladder and surrounds the bladderopening so as to provide access to the interior of bladder 13 throughannular member 15 and the bladder opening. Annular member 15 includes acylindrically shaped annular fitment 14, also preferably made of nylon,that surrounds the opening through the annular member 15 and extendsaway from the top surface of annular member 15. As will be illustratedin more detail in FIG. 5B, annular fitment 14 is utilized to releasablyattached bladder 13 to dispenser tube 11.

FIG. 5 A shows dispenser tube 12 after it has been partially insertedthrough annular member and fitment 14 and 15, respectively, and into theinterior of bladder 13, with two opposite sides of bladder 13 furled orrolled up so as to form the two opposing furled tubes, 13A and 13B, ofrolled up bladder material, with opposite edges, 16A and 16B, of thebladder lying adjacent to the inside surface of furled tubes, 13A and13B, respectively. And, FIG. 5B illustrates the completed assembly ofdispenser tube assembly 10, with dispenser tube 12 completely disposedwithin the interior of bladder 13 and with bladder 13 releasablyconnected to dispenser valve 11. Dispenser tube assembly 10 is furtherillustrated in the partial cross-sectional plan view diagram of FIG. 5C,showing bladder 13 releasably connected to dispenser valve 11 byinserting fitment 14 between resilient O-ring 25 and flange 21 ofdispenser valve 11, and with the resiliency of O-Ring 25 providing asufficient radial force to maintain the connection between fitment 14and flange 21 but, at the same time, allowing bladder 13 to be easilyremoved from the dispenser valve by applying a slight downward force onthe bladder. In an alternative embodiment, as shown in FIG. 5D, bladder13 can be rolled or furled around dispenser tube 11, thereby forming asingle furled tube, with opposite edges, 16A and 16B, of the bladderlying adjacent to the outside surface of the single furled tube.

Once dispenser tube assembly 10 has been assembled, the assembly can beinserted through the opening within valve attachment collar 4 as shownin FIG. 1. Then, as shown in the partial cross-sectional diagram ofFIGS. 6A through 6C and in the cross-sectional diagram of FIGS. 9A and9B, dispenser tube assembly 10 can be releasably connected to keg body 2by attaching dispenser valve 11 to the valve attachment collar 4attached to the top portion of the keg body. Two arcuate-shaped valveflange segments, integral with annular flange 21 that is integral withdispenser valve 11, extend radially outward and away from annular flange21, with each flange segment extending approximately 90° around annularflange 21 and positioned such that each end of a flange segment isspaced 90° away from the end of an adjacent flange segment. A pairradially extending cantilever arms 29 is formed within annular flange 21such that the end of each cantilever arm can flex in a verticaldirection when subjected to a vertical load, with the cantilever armspositioned 180° apart and with each arm extending through a respectiveflange segment. Two arcuate-shaped collar flange segments, integral withthe axially extending inside sidewall of collar 4, extend radiallyinward, with each collar flange segment extending approximately 90°around the inside sidewall of collar 4 and positioned such that each endof a collar flange segment is spaced 90° away from the end of anadjacent collar flange segment. Each collar flange segment has a varyingthickness, as measured in an axial direction parallel to the sidewall ofcollar 4, with the thickness increasing in a clockwise direction alongthe flange segment, thereby creating a ramp-like surface on theunder-side surface of each collar flange segment. Finally, a notch isformed through each collar flange segment and is positioned adjacent tothe thicker end of the flange. In operation, dispenser valve 11 isreleasably attached to collar 4 by inserting the valve flange segmentsbetween the collar flange segments, as shown in FIG. 6B, and rotatingvalve 11 in a clockwise direction, as illustrated in FIG. 6C, whichcauses each of the valve's cantilever arms to slide along a respectivecollar's ramp-like surface until the pair of cantilever arms 29 engage arespective collar flange notch. When the beer has been completelydispensed from the reusable beer keg 1, the dispenser tube assembly 10is easily removed from keg body 2 by simply pressing down on the ends ofthe pair of cantilever arms, thereby releasing the arms from the collarflange notches, simultaneously rotating the dispenser valve 11 in acounter-clockwise direction, and lifting the dispenser tube assemblyfrom keg body 2.

Once dispenser tube assembly has been attached to keg body 2, as shownin FIG. 6A, the reusable beer keg 1 is ready to be filed with anddispense beer. During the operation of filling beer keg 1 with beer,beer flows through an open dispenser valve 11 and into the interior ofbladder 13. As the beer continues to flow into the bladder, bladdertubes 13A and 13B begin to unfurl as shown in FIG. 7, and when thefiling operation is completed, the beer will have caused bladder 13 tounfurl until the outside surface of the bladder comes into contact withthe inside surface of keg body 2, as shown in FIG. 8.

Referring now to FIGS. 5C, 9A and 9B, a more detailed description of theoperation of dispenser valve 11 is presented. When a beer tap (notshown) is connected to the inlet port 28 of dispenser valve 11, the tappresses on the valve body's outer annular seal 20 causing the seal anddispenser tube 12 to move in a downward direction against the force ofouter valve spring 25 and to thereby open the valve by creating an valveinlet gap A between the valve body 20 and seal 23. Once dispenser valve11 is in the open configuration, pressurized beer can be delivered tothe interior of bladder 13 through the valve inlet gap. And, as the beerenters bladder 13, it causes the bladder to unfurl until outside surfaceof the bladder contacts substantially the entire inside surface of kegbody 2, at which point beer keg 1 has been filled with beer. In order todispense the beer, pressurized CO2 gas is supplied through the beer tapand valve inlet gap A. A tap spigot can then be opened, which depressesseat 24 downward against interior valve spring 27, thereby creating avalve outlet gap B within the dispenser valve 11 between seat 24 and theseal 23. Beer is then forced from the bladder up through the bottomopening of dispenser tube 12, through the valve outlet gap B withindispenser valve 11, and out of the tap spigot.

When the beer keg has been emptied, it can be returned to the brewerywhere dispenser tube assembly 10 is removed from keg body 2 by unlockingdispenser valve 11 from its engagement with valve attachment collar 4.Used disposable bladder 13 can then be removed from its engagement withdispenser valve 11 by pulling on the bladder in a direction generallyparallel to dispenser tube 12 in order to cause valve fitment 14 toslide out from between O-Ring 25 and flange 21 of dispenser valve 11.Used bladder 13 is then disposed of in any appropriate manner for therecycling of plastic material generally. Dispenser valve 11 anddispenser tube 12 are then cleaned and, along with the use of a newreusable bladder 13, are used to reassemble dispenser tube assembly 10as previously described. Then the reassembled dispenser tube assembly 10is attached to the used beer keg body 2 by connecting the assembly tothe keg body as described above. In this regard, there is no need toclean the used beer keg body because the beer does not come into contactwith the keg body; rather the beer only contacts the interior surface ofbladder 13. The used beer keg 1 is now ready for being refilled withbeer and delivered to a commercial establishment.

Now, referring back to FIG. 6A, in another embodiment a temperaturesensor and display device 30, such as thermochromatic liquid crystaltemperature indicator, can be disposed within an opening through the topportion of keg body 2. Further, a heat transfer strip 31, preferablymade of aluminum or an aluminum alloy, having a curved top portion and astraight bottom portion, can be disposed adjacent to the inside surfaceof keg body 2, with the curved top portion positioned so as to contactthe bottom surface of sensor and display device 30 and its straightbottom portion positioned approximately half way down the insidevertical surface of keg body 2. When beer is supplied to the interior ofdisposable bladder 13, causing the bladder to unfurl and its outsidesurface to contact the inside surface of keg body 2, the outside surfaceof the bladder also comes into contact with heat transfer strip 31. Inthis regard, the temperature of the beer when it leaves the brewery willbe normally maintained at a target temperature of about 38° F. After arelatively brief period of time, the temperature of heat transfer strip31 will become approximately equal to the temperature of the beer, and atemperature of the beer will be displayed on sensor and display device30, in this case it will display 38° F. As the temperature of the beerinside bladder 13 changes, the change is sensed heat transfer strip 31and sensor and display device 30 and displayed on the device. In thismanner, it can be accurately and easily determined whether thetemperature of the beer in the keg has changed from its “target”temperature by simply looking at the display on temperature sensor 30.

FIGS. 10A and 10B illustrate that the beer kegs of the present inventioncan be easily stacked together and held firmly in place. A top portionof cylindrical member 3A, attached to keg body 2, contains four arcuateshaped axially extending flanges that are integral with cylindricalmember 3A and are equally spaced around its perimeter, with the topsurface of each of the flanges being formed into a convex shape. Eachflange also contains an elongate top slot that extends through theflange. Similarly, a bottom portion of cylindrical member 3B, attachedto keg body 2, contains four arcuate shaped axially extending feet thatare integral with cylindrical member 3B and are equally spaced aroundits perimeter, with the bottom surface of each of the feet being formedinto a concave shape. Each foot also contains an elongate bottom slotthat extends through the flange. As shown in the figures, when the beerkegs are stacked on top of each other, the concave shape of the bottomsurface of the feet approximately mates with the convex shape of the topsurface of the top flanges, thereby providing some stability to thestack. Further stability can be provided by using a resilient strap 35,having a hook portion on each end, with the hook portion on one end ofthe strap engaging with a top slot and with the hook portion on theother end of the strap engaging with a bottom slot. Similarly, one ormore additional resilient straps 35 can be attached in like fashionaround keg body 2. In addition to implementing the feature of being ableto further secure the stack of kegs, the top and bottom elongate slotscan also be used as handholds.

Although a preferred embodiment and other embodiments have beendescribed, it will be recognized by those skilled in the art that otherembodiments and features can be provided without departing from theunderlying principals of those embodiments. The scope of the inventionis defined by the appended claims.

We claim:
 1. A method for using a reusable beer keg, comprising thesteps of: a) providing a hollow beer keg body with the keg body having akeg opening for providing access to the interior of the keg body; b)assembling a dispenser tube assembly by disposing a dispenser tubethrough an opening through a disposable bladder, with one end of thedispenser tube extending into the interior of the bladder, and with thebladder opening releasably secured to a dispenser valve connected to theother end of the dispenser tube; c) disposing the dispenser tubeassembly through the keg body opening such that the dispenser valvereleasably engages the keg body and the dispenser tube extends into theinterior of the keg body, thereby creating the reusable beer keg; d)dispensing beer into the interior of the bladder; e) dispensingpressurized gas into the interior of the bladder, causing the beer toflow up through the dispenser tube; f) disassembling the reusable beerkeg after it has dispensed the beer by releasing the dispenser valvefrom its engagement with the keg body, removing the dispenser tubeassembly from the interior of the keg body, and releasing the bladderfrom its engagement with the dispenser valve; g) disposing of thedisposable bladder; h) cleaning the dispenser valve and dispenser tube;and i) reassembling the reusable beer keg as in steps (b) and (c) aboveby reusing the keg body, cleaned dispenser valve and dispenser tube, andusing a new disposable bladder.